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81.
动物鸣叫声计算机分析 总被引:5,自引:1,他引:4
动物鸣叫声计算机分析姜仕仁,丁平,施青松诸葛阳(杭州大学生物科学与技术系310012)ComputerAnalysisofAnimal’sCallingSound¥JiangShiren,Ding,Ping,ShiQingsong,ZhugeYang... 相似文献
82.
The effect of the protein structure of ( on its incorporation into liposome membranes was investigated as follows: the catalytic α-subunit of ( was split into low-molecular weight fragments by trypsin treatment and the digested enzyme was reconstituted at the same protein concentration as intact control enzyme. The reconstitution process was quantified by the average number of intramembrane particles appearing on concave and convex fracture faces after freeze-fracture of the ( liposomes. The number of intramembrane particles as well as their distribution on concave and convex fracture faces is not modified by the proteolysis. In contrast, the ATPase activity and the transport capacity of the ( decrease progessively with increasing incubation times in the presence of trypsin and are abolished when the original 100 000 molecular weight α-subunit is no longer visible by sodium dodecylsulfate gel electrophoresis. Apparently, functional ( with intact protein structure and digested, non functional enzyme consisting of fragments of the α-subunit reconstitute in the same manner and to the same extent as judged by freeze-fracture analysis. We conclude that, while trypsin treatment modifies the ( molecule in a functional sense, it appears not to modify its interaction with the bilayer in producing intramembrane particles. On the basis of our results, we propose a lipid-lipid interaction mechanism for reconstitution of (. 相似文献
83.
七星瓢虫生殖的观察 总被引:2,自引:0,他引:2
近年来,在我国各地区一个“以虫治虫”的群众运动正在蓬勃展开。实践证明它可作为“综合防治”总方针中的重要一环。以瓢治蚜已经在广大棉区收到较好的效果,深受广大贫下中农的欢迎。本文介绍七星瓢虫(Coccinella septempunctata L.)一些生殖特点,作为瓢虫饲养繁殖时参考。 观察实验是在北京、安阳两个地区进行的,室内和室外观察相结合,加上必要的镜检帮助了解一些机体内部的状况。实验材料七星瓢虫根据观察的需要,有的是室外采集的,有的是室内繁殖饲养的,或是室外采集室内饲养。所用饲料蚜虫,有菜蚜、桃蚜、麦蚜等。在观察实验过程中得到安阳县生防站同志们的热情帮助。 相似文献
84.
Summary Studies on the effects of pretreatment with aldosterone on the incorporation of3H leucine or3H methionine into proteins in renal slices were carried out in Joklik-modified minimal essential medium. Administration of aldosterone (2 g/100 g body wt) to adrenalectomized rats increased3H leucine incorporation into trichloroacetic acid insoluble fractions of crude homogenates of cortical slices by 15.5±0.4% and of medullary slices by 53.5±1.3%. No increase in isotope incorporation was observed in slices of renal papilla or spleen prepared from the same rats. Aldosterone had no effect on the3H-leucine content of the trichloroacetic acid-soluble fractions of all three renal zones and the spleen. The dose of aldosterone that elicited a half-maximal increase in3H-methionine incorporation into proteins of renal medullary slices (0.45 g of aldosterone/100 g body wt) was indistinguishable from that needed to elicit a halfmaximal increase in the urinary K+/Na+ ratio (0.35 g of aldosterone/100 g body wt). Dexamethasone, a potent glucocorticoid, at a dose of 0.8 g/100 g body wt did not augment3H-leucine incorporation into renal medullary proteins but was effective at 8 g/100 g body wt. Spirolactone (SC-26304), a potent anti-mineralocorticoid, abolished the effect of aldosterone on amino acid incorporation into medullary proteins when administered at a 100-fold higher dosage [i.e., 80 gvs. 0.8 g (per 100 g body wt)]. These results imply that the action of aldosterone on amino acid incorporation is mediated by the mineralocorticoid rather than the glucocorticoid pathway, presumably the mineralocorticoid receptors. Moreover, pretreatment of the rats with actinomycin D (70–80 g/100 g body wt) erased the effect of aldosterone (0.8 g/100 g body wt) on amino acid incorporation into medullary proteins.In paired experiments with3H and35S methionine, aldosterone (0.8 g/100 g body wt) increased methionine incorporation into trichloroacetic acid precipitable proteins of subcellular fractions of the renal medulla. The effect of aldosterone on incorporation of methionine into medullary cytosol proteins was analyzed further by polyacrylamide gel electrophoresis at pH 8.3 in tris-glycine buffer. The gel profiles indicate that aldosterone significantly increased methionine incorporation into at least one protein (independent of the isotope) with a molecular weight of 31,000. This increase was inhibited by either pretreatment of the rat with actinomycin D (70–80 g/100 g body wt or SC-26304 (80 g/100 g body wt). Dexamethasone (0.8 g/100 g body wt) did not increase incorporation of methionine into the medullary cytosol proteins resolved by polyacrylamide gel electrophoresis. 相似文献
85.
Summary The possible induction of renal citrate synthase (E.C. 4.1.3.7), by aldosterone was evaluated in the adrenalectomized rat. Three hours after administration of aldosterone (0.8 g/100 g body wt), renal cortical and medullary citrate synthase activity was significantly increased as reported previously by Kinne and Kirsten (Kinne, R., Kirsten, R. 1968.Pfleugers Arch. 300:244). In contrast, no change in this activity was detected in the renal papilla or the liver, under the same conditions. Kinetic analysis revealed that injection of aldosterone had no effect on theK
m
s for acetyl-CoA and oxalacetate but augmentedV
max of renal medullary citrate synthase activity by 40%. The aldosterone-dependent increase in medullary citrate synthase activity was proportionate to the associated increase in the quantity of antiserum (specific for citrate synthase) required for half-maximal immuno-precipitation.The possibility that aldosterone induced the synthesis of citrate synthase was evaluated in two sets of experiments. In the first set, adrenalectomized rats were injected intraperitoneally with either aldosterone (0.8 g/100 g body wt) or the diluent, and simultaneously with3H or35S methionine (500 Ci/rat). The isotopes were reversed in about half of the experiments. Three hours after the injection, renal citrate synthase was isolated by ATP-sepharose column chromatography and immuno-precipitation with the specific antiserum. Aldosterone augmented methionine incorporation into renal citrate synthase by 55% but had no effect on incorporation into the hepatic enzyme. In the second set, adrenalectomized rats were injected with either aldosterone (0.8 g/100 g body wt) or the diluent, the kidneys were removed 1 hr later and medullary slices were incubated in either3H-or35S-methionine at 20° for 2 hr. Mitochondrial citrate synthase was isolated either by ATP-sepharose column chromatography and immuno-precipitation, or by polyacrylamide gel electrophoresis. Aldosterone increased methionine incorporation into the immuno-precipitates by 30% and into the enzyme peak resolved by polyacrylamide gel electrophoresis by 43%. The latter increase was eliminated by prior administration of either actinomycin D (70–80 g/100 g body wt) or spirolactone (SC-26304) (80 g/100 g body wt). An equimolar dose of dexamethasone (0.8 g/100 g body wt) had no effect on the isotope ratio associated with citrate synthase activity in the polyacrylamide gels. 相似文献
86.
蓖麻蚕蛹卵巢发育过程中亚细胞组分核酸和蛋白质的代谢与脑激素的影响 总被引:1,自引:0,他引:1
在20℃条件下,蓖麻蚕蛹期发育需14天,接近发育完成的卵巢中各亚细胞组分中DNA、RNA和蛋白质含量迅速增长。经手术去脑后的蓖麻蚕无脑蛹卵巢不发育,其卵巢中上述成分的含量皆处于蛹早期水平。经脑激素处理后的无脑蛹卵巢即可迅速发育,在处理后18—20天,卵巢发育可接近正常水平,但较晚。在电镜下观察到的游离多核糖体呈二到七聚体,其紫外光谱特性为A260/A280=1.70;A240/A280=1.27。将脑激素注射到无脑蛹中去,可促使卵巢中游离多核糖体含量的增加。 相似文献
87.
从土牛膝(Achyraanthes bidentata Bl.)的根中分离到一种新的生物碱——土牛膝碱(ubidenine),通过波谱方法测定出土牛膝碱的化学结构为5,6—二氢化—2,3,10,11—四甲氧基—二苯并[a,g]—喹嗪盐(1)。 相似文献
88.
89.
本文通过对枯草芽孢杆菌BR151衍生株与北京棒杆菌1134衍生株的赖氨酸高产融合子Q4413株的形态学、生理生化特性等方面的研究,揭示了融合子与双亲株在这些方面的差异,为Q4413株确系双亲株的重组子或新的融合子增加了佐证. 相似文献
90.
本文分析30例慢性肺心病心衰并呼衰患者(心衰并呼衰组)及30例慢性肺心病心衰无呼衰患者(心衰无呼哀组)和慢性肺心病死亡组的血清甲状腺激素水平。结果表明心衰并呼衰组T_3、T_4水平均值显著低于心衰无呼衰组和健康组,心衰无呼衰组T_3水平均值显著低于健康组,肺心病死亡组T_3、T_4水平均值显著低于存活组,并发现血清T_3、T_4水平与动脉血氧分压(PaO_2)呈正相关。作者认为T_3明显降低是重症肺心病的损伤性结果,预示病情严重,预后差。而T_4明显下降,可能是死亡的信号之一。 相似文献